A novel role for DYX1C1, a chaperone protein for both Hsp70 and Hsp90, in breast cancer

With three consecutive tetratricopeptide repeat (TPR) motifs at its C-terminus essential for neuronal migration, and a p23 domain at its N-terminus, DYX1C1 was the first gene proposed to have a role in developmental dyslexia. In this study, we attempted to identify the potential interaction of DYX1C1 and heat shock protein, and the role of DYX1C1 in breast cancer. GST pull-down, a yeast two-hybrid system, RT-PCR, site-directed mutagenesis approach. Our study initially confirmed DYX1C1, a dyslexia related protein, could interact with Hsp70 and Hsp90 via GST pull-down and a yeast two-hybrid system. And we verified that EEVD, the C-terminal residues of DYX1C1, is responsible for the identified association. Further, DYX1C1 mRNA was significantly overexpressed in malignant breast tumor, linking with the up-regulated expression of Hsp70 and Hsp90. These results suggest that DYX1C1 is a novel Hsp70 and Hsp90-interacting co-chaperone protein and its expression is associated with malignancy.